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collected between approximately 5 feet bgs and 30 feet bgs to assess the presence of petroleum hydrocarbons in soils above the groundwater table. Soil samples for laboratory analysis will be collected at five-foot intervals beginning at 5 feet bgs, and at changes in soil lithology with obvious contamination. During sampling of boring HP3, a log of the boring will be maintained to document the soil lithologies encountered and conditions of the soils with respect to the presence of petroleum hydrocarbons. Portions of the collected soil samples will be field screened for undifferentiated volatile organic compounds (UVOC) using a photo-ionization detector (PID). Soil samples will be collected in acetate liners, capped and labeled with the borehole number, sample depth, project number and time and date of collection. Results of the PID screening will also be documented on the boring. Field procedures for soil sample collection and retention are further described in Appendix C. HYDROPUNCH GROUNDWATER SAMPLING Borings HP3 and HP4 will be advanced to the target groundwater sampling intervals of 40 feet bgs and 60 feet bgs in HP3, and 40 feet bgs, 60 feet bgs and 80 feet bgs in HP4. Collection of groundwater grab samples will conducted using precleaned drive rods equipped with a hydropunch sampling tool that will be advanced through the drive rods to expose a 4-foot section of hydropunch screen for collection of the groundwater samples. Groundwater samples will be collected using dedicated 0.25-inch diameter Teflon tubing fitted with a stainless-steel check valve. Collected water samples will be transferred to laboratory-supplied 40 milliliter vials. Each sample vial will be labeled with project specific information and stored in an insulated chest pending transport to the analytical laboratory under chain-of-custody documentation. Following collection of the groundwater grab samples, each hydropunch boring will be sealed by pumping neat cement through the drive rods during withdrawal. Sealing of borings will be completed under inspection by a representative from the SJCEHD. Each boring location will be surface patched with asphalt, concrete or soil to match the existing surface conditions. LABORATORY ANALYSES All collected soil and groundwater samples will be submitted to a State-certified laboratory for analysis for standard list VOC and gasoline range organics (TPH-GRO) in general accordance with EPA method 826013. Samples will be transported to the analytical laboratory under chain- of-custody documentation. DATA EVALUATION AND REPORTING Upon receipt of all soil and groundwater analytical reports, the data will be evaluated with respect to the source of any petroleum hydrocarbons detected in the soil and groundwater. A report will be prepared to document the results of the soil and hydropunch groundwater sampling and present a discussion of the data with regards to a potential off-Site source of petroleum hydrocarbons. The report will be submitted to the RWQCB and uploaded onto the SWRCB's "GeoTracker"website. FREY Environmental,Inc. 10 Project No. 1095-01